gg_account t1_je0pbaf wrote on March 28, 2023 at 4:00 PM

Reply to comment by FTL_Diesel in James Webb Space Telescope finds no atmosphere on Earth-like TRAPPIST-1 exoplanet by locus_towers

Interesting thanks! The data I was looking at was apparently from 2018. So it seems the jump to "there must be a thick atmosphere" came from an assumption that the planet had as much iron as Earth?

FTL_Diesel t1_je17m5v wrote on March 28, 2023 at 5:55 PM

The observation planning assumed that -1b would have an atmosphere similar to Venus. This is why they observed five eclipses, since a Venus-like atmosphere would have been just detectable after combining all that data. What ended up happening is that the dayside of the planet is much hotter than predicted for a Venus-like atmosphere, and the eclipse was actually detected right off the bat on the first observation!